Electrical power supply device and method of operating same

ABSTRACT

An electrical power supply device is configured to communicate with a start-stop controller that automatically shuts down and restarts an internal combustion engine in a vehicle. The device includes a DC-DC power convertor and a device controller. The DC-DC power convertor is configured to produce a first voltage or a second voltage that is less than the first voltage. The device controller which causes the DC-DC power convertor to produce the first voltage in response to a run signal from the start-stop controller and also causes the DC-DC power convertor to produce the second voltage in response to a stop signal from the start-stop controller.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application and claims the benefit ofco-pending U.S. patent application Ser. No. 16/203,717, filed Nov. 28,2018, which was a continuation-in-part application and claimed thebenefit patent application Ser. No. 15/954,851, filed Apr. 17, 2018, theentire disclosure of each of which is hereby incorporated herein byreference.

TECHNICAL FIELD OF THE INVENTION

The invention generally relates to an electrical power supply device andmethod of operating the electrical power supply device.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The present invention will now be described, by way of example withreference to the accompanying drawings, in which:

FIG. 1 is a schematic diagram of an electrical power supply device,according to one embodiment; and

FIG. 2 is a flow chart of a method of operating the electrical powersupply device of FIG. 1, according to one embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings. In the following detaileddescription, numerous specific details are set forth in order to providea thorough understanding of the various described embodiments. However,it will be apparent to one of ordinary skill in the art that the variousdescribed embodiments may be practiced without these specific details.In other instances, well-known methods, procedures, components,circuits, and networks have not been described in detail so as not tounnecessarily obscure aspects of the embodiments.

The Universal Serial Bus (USB) has evolved from a data interface capableof supplying limited power to a primary provider of power with a datainterface. Today many devices charge or get their power from USB portscontained in laptops, cars, aircraft or even wall sockets. USB hasbecome a ubiquitous power socket for many consumer devices such ascellular telephones, digital media players and/or other hand-helddevices. Users utilize USB to fulfil their requirements not only interms of data but also to provide power to, or charge, their devicessimply, often without the need to load a driver, in order to carry out“traditional” USB functions.

The USB Power Delivery (PD) Specification enables the maximumfunctionality of USB by providing more flexible power delivery, e.g. forbattery charging, along with data over a single cable. Its aim is tooperate with and build on the existing USB ecosystem. The USB PowerDelivery Specification 3.0 is published by the USB Implementer's Forum,Inc and is incorporated by reference herein.

In order to meet stringent fuel economy and emission standards,automotive original equipment manufacturers (OEMs) have includedstart-stop technology in their vehicles that automatically shuts downand restarts the internal combustion engine to reduce the amount of timethe engine spends idling, thereby reducing fuel consumption andemissions of the vehicle.

OEMs have imposed requirements for a USB PD device powered by thevehicle battery requires it to continue to supply power to the consumerUSB device during “Start/Stop” transients in which the vehicle batteryvoltage temporarily dips down to as low as 6 volts to simulate thevehicle cranking during a warm start. During this transient, the USB PDdevice is expected to continue to function with no disruption to theconsumer experience. Supplying a consistent power level during thetransient will cause the current input to the PD device to rise tolevels that may exceed current limits of the wiring, connectors, and/orcircuit protection devices, e.g. fuses, circuit breakers, of the PDdevice that would cause a disruption of the consumer experience, e.g.opening a fuse and thereby causing a shutdown of the PD device.

Some original equipment vehicle manufacturers (OEMs) monitor the powerbeing supplied by the vehicle's electrical power system and inhibit thestart-stop controller if the power supplied exceeds a power threshold.

A proposed innovative solution is to provide a signal from the vehicleto the USB PD device to indicate the power state of the vehicle. Duringthe normal vehicle run mode the vehicle voltage is expected to betypically in the 12-14 volt range and a buck-boost DC-DC converter cangenerate a higher voltage output that has a greater voltage than thevehicle voltage that can be used by the consumer charging device in a“fast charge” mode. When the vehicle enters or intends to enter thestop/start mode, i.e. the vehicle has stopped moving and automaticallyturns off the engine, the change in mode is communicated by a signalfrom the vehicle to a controller in the USB PD device and the USB PDdevice then renegotiates the charging contact with the consumer deviceto provide a lower output voltage for “normal” charging operation. Whenthe car subsequently experiences a crank cycle transient, the buckconverter is able to maintain the lower output voltage without exceedingcurrent limits and without interrupting the charging session. After theengine starts and returns to the run mode, the USB PD device is againnotified via another signal and returns to the higher voltage output.

FIG. 1 illustrates an electrical power supply device, e.g. a UniversalSerial Bus (USB) power delivery (PD) device, hereinafter referred to asthe PD device 10 that is designed for use in a motor vehicle 12. The PDdevice 10 may be used to support battery charging of USB enabled devicesin the vehicle 12 (not shown). The PD device 10 includes a boost-buckDC-DC power convertor, hereinafter referred to as the DC convertor 14,that receives an input voltage from a vehicle's electrical system. Inother embodiments of the invention, the PD device 10 may be a buck onlyDC-DC power convertor. The output voltage can by one of at least twodifferent voltages, a higher voltage, e.g. a 20-volt output to support afast USB charge rate, or a lower voltage, e.g. a 5-volt output tosupport a normal USB charge rate.

The PD device 10 also includes a device controller 16 that is incommunication with the DC convertor 14. The device controller 16 has oneor more processors and memory. The processors may be microprocessors,application specific integrated circuits (ASIC), or built from discretelogic and timing circuits (not shown). Software instructions thatprogram the processors may be stored in a non-volatile (NV) memorydevice (not shown). The NV memory device may be contained within themicroprocessor or ASIC or it may be a separate device. Non-limitingexamples of the types of NV memory that may be used include electricallyerasable programmable read only memory (EEPROM), masked read only memory(ROM), and flash memory.

The PD device 10 also includes interface circuitry 18, such as acontroller area network (CAN) transceiver, a local interconnect network(LIN) transceiver, a USB transceiver, and/or an input voltage detectioncircuit, e.g. an analog/digital convertor circuit, to allow the PDdevice 10 to establish electrical communication with other deviceswithin the vehicle 12.

The PD device 10 is in communication with a start-stop controller 20 viathe CAN transceiver or the LIN transceiver. The memory further includesinstructions which cause the device controller 16 to command the DCconvertor 14 to output the higher output voltage in accordance with thedevice controller 16 receiving a run signal from the start-stopcontroller 20. The reception of the run signal causes the devicecontroller 16 to command the DC convertor 14 to output the lower outputvoltage in accordance with the device controller 16 receiving a stopsignal from the start-stop controller 20. The run signal indicates thatthe IC engine 22 is running, therefore the input voltage will remainequal to or greater than the threshold voltage. The stop signalindicates that the IC engine 22 is not running and that the inputvoltage may drop to less than the threshold voltage, e.g. during acranking transient.

In another embodiment, the PD device 10 is disposed within a USB portthat is in communication with a USB hub 24 that is in communication withthe start-stop controller 20. The memory includes instructions whichcause the device controller 16 to command the DC convertor 14 to outputthe higher output voltage in accordance with the device controller 16receiving a first USB signal from the USB hub 24 indicating that the USBhub 24 has received a run signal from the start-stop controller 20 andwhich cause the device controller 16 to command the DC convertor 14 tooutput the lower output voltage in accordance with the device controller16 receiving a second USB signal from the USB hub 24 indicating that theUSB hub 24 has received a stop signal from the start-stop controller 20.

In yet another embodiment, the PD device 10 includes an input voltagedetection circuit that is in communication with the vehicle powersupply, e.g. vehicle battery (not shown) and the device controller 16.The input voltage detection circuit is configured to determine the inputvoltage to the PD device 10 from the vehicle battery and transmit thatinformation to the device controller 16. The memory includes additionalinstructions which cause the device controller 16 to command the DCconvertor 14 to output the higher output voltage when the input voltagedetection circuit determines that the input voltage is greater than athreshold voltage, e.g. 9.5 or 10 volts and which cause the devicecontroller 16 to command the DC convertor 14 to output the lower outputvoltage when the input voltage detection circuit determines that theinput voltage is less than the threshold voltage.

FIG. 2 illustrates a method 100 of operating the PD device 10 having theDC convertor 14 and the device controller 16 and in communication withthe start-stop controller 20. The method 100 includes the followingsteps:

STEP 102, RECEIVE A SIGNAL FROM THE START-STOP CONTROLLER, includes thePD device 10 receiving a signal from the start-stop controller 20;

STEP 104, DETERMINE WHETHER THE SIGNAL IS A RUN SIGNAL OR A STOP SIGNAL,includes the device controller 16 determining whether the signal is arun signal or a stop signal;

STEP 106, PRODUCE A FIRST OUTPUT VOLTAGE, includes the PD device 10producing the higher output voltage via the DC convertor 14 inaccordance with the device controller 16 determining that the signal isthe run signal; and

STEP 108, PRODUCE A SECOND OUTPUT VOLTAGE, includes the PD device 10producing a second output voltage via the DC convertor 14 which is lessthan the first output voltage in accordance with the device controller16 determining that that the signal is the stop signal.

According to a particular embodiment, if the PD device 10 has negotiateda PD contract with a consumer device (not shown) at 100 watts i.e. theoutput voltage is 20 volts and current capacity is 5 amperes and astart-stop event occurs, in the vehicle 12, i.e. the start-stopcontroller 20 sends a stop signal, the PD device 10 will change thepower negotiation from 100 watts to 15 watts, i.e. output voltage is 5volts and current capacity is 3 amperes, thereby reducing power requiredto be supplied to the PD device 10 by the vehicle 12 and reducing thecurrent drawn by the PD device 10 and staying within the limits of thecircuits current protection devices. Per the USB PD specifications, theconsumer device will select the new 15-watt capability. After thestop-start event ends, i.e. the start-stop controller 20 sends a runsignal, the PD device 10 will renegotiate 100-watt capability and theconsumer device will choose highest power needed.

Accordingly, an electrical power supply device, e.g. a USB PD device 10,and a method 100 of operating such a device is provided. The deviceprovides the benefit of a USB PD device 10 that is capable ofuninterrupted supply of power from the PD device 10 to a consumer USBdevice during a start-stop event in a vehicle 12. This USB PD device 10may also provide the benefit of reducing or “shedding” electrical loadfrom the vehicle's electrical system by reducing, but not discontinuing,the power supplied to the USB consumer device, e.g. reducing powersupplied from 100 watts to 15 watts, which may allow the start-stopcontroller 20 to enter the start-stop mode.

While this invention has been described in terms of the preferredembodiments thereof, it is not intended to be so limited, but ratheronly to the extent set forth in the claims that follow. For example, theabove-described embodiments (and/or aspects thereof) may be used incombination with each other. In addition, many modifications may be madeto configure a particular situation or material to the teachings of theinvention without departing from its scope. Dimensions, types ofmaterials, orientations of the various components, and the number andpositions of the various components described herein are intended todefine parameters of certain embodiments and are by no means limitingand are merely prototypical embodiments.

Many other embodiments and modifications within the spirit and scope ofthe claims will be apparent to those of skill in the art upon reviewingthe above description. The scope of the invention should, therefore, bedetermined with reference to the following claims, along with the fullscope of equivalents to which such claims are entitled.

As used herein, ‘one or more’ includes a function being performed by oneelement, a function being performed by more than one element, e.g., in adistributed fashion, several functions being performed by one element,several functions being performed by several elements, or anycombination of the above.

It will also be understood that, although the terms first, second, etc.are, in some instances, used herein to describe various elements, theseelements should not be limited by these terms. These terms are only usedto distinguish one element from another. For example, a first contactcould be termed a second contact, and, similarly, a second contact couldbe termed a first contact, without departing from the scope of thevarious described embodiments. The first contact and the second contactare both contacts, but they are not the same contact.

The terminology used in the description of the various describedembodiments herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used in thedescription of the various described embodiments and the appendedclaims, the singular forms “a”, “an” and “the” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise. It will also be understood that the term “and/or” as usedherein refers to and encompasses any and all possible combinations ofone or more of the associated listed items. It will be furtherunderstood that the terms “includes,” “including,” “comprises,” and/or“comprising,” when used in this specification, specify the presence ofstated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof.

As used herein, the term “if” is, optionally, construed to mean “when”or “upon” or “in response to determining” or “in response to detecting,”depending on the context. Similarly, the phrase “if it is determined” or“if [a stated condition or event] is detected” is, optionally, construedto mean “upon determining” or “in response to determining” or “upondetecting [the stated condition or event]” or “in response to detecting[the stated condition or event],” depending on the context.

Additionally, while terms of ordinance or orientation may be used hereinthese elements should not be limited by these terms. All terms ofordinance or orientation, unless stated otherwise, are used for purposesdistinguishing one element from another, and do not denote anyparticular order, order of operations, direction or orientation unlessstated otherwise.

We claim:
 1. An electrical power supply device configured to communicatewith a start-stop controller that automatically shuts down and restartsan internal combustion engine in a vehicle, comprising: a DC-DC powerconvertor configured to produce a first voltage or a second voltage thatis less than the first voltage; and a device controller which causes:the DC-DC power convertor to produce the first voltage in response to arun signal from the start-stop controller, and the DC-DC power convertorto produce the second voltage in response to a stop signal from thestart-stop controller.
 2. The electrical power supply device accordingto claim 1, wherein a maximum value of the first voltage is 20 volts anda minimum value of the second voltage is 3.2 volts.
 3. The electricalpower supply device according to claim 1, further comprising interfacecircuitry to communicate between the start-stop controller and thedevice controller, wherein the interface circuitry comprises at leastone selected from a list consisting of a controller area network (CAN)transceiver, a local interconnect network (LIN) transceiver, a UniversalSerial Bus (USB) transceiver, and an input voltage detection circuit. 4.The electrical power supply device according to claim 1, wherein theelectrical power supply device comprises a USB transceiver and whereinthe device controller causes: the DC-DC power convertor to output thefirst voltage in response to the USB transceiver receiving a first USBsignal indicating the run signal from the start-stop controller; and theDC-DC power convertor to output the second voltage in response to theUSB transceiver receiving a first USB signal indicating the run signalfrom the start-stop controller.
 5. The electrical power supply deviceaccording to claim 1, wherein the electrical power supply devicecomprises a USB transceiver and wherein the device controller:negotiates a power delivery contract with a consumer device at a firstoutput power in response to the USB transceiver receiving a first USBsignal indicating the run signal from the start-stop controller, andrenegotiates the power delivery contract with the consumer device at asecond output power less than the first output power in response to theUSB transceiver receiving a first USB signal indicating the run signalfrom the start-stop controller.
 6. The electrical power supply deviceaccording to claim 5, wherein the device controller renegotiates thepower delivery contract with the consumer device at the first outputpower in response to the USB transceiver receiving the first USB signalindicating the run signal from the start-stop controller.
 7. Theelectrical power supply device according to claim 5, wherein the firstoutput power is 100 watts and the second output power is 15 watts. 8.The electrical power supply device according to claim 1, wherein thedevice controller further comprises a processor and non-volatile memorywhich contains instructions which causes the DC-DC power convertor toproduce the first voltage in response to a run signal from thestart-stop controller and the DC-DC power convertor to produce thesecond voltage in response to a stop signal from the start-stopcontroller.
 9. An electrical power supply device, comprising: a DC-DCpower convertor configured to receive an input voltage and produce afirst voltage or a second voltage that is less than the first voltage; adevice controller; and an input voltage detection circuit, wherein thedevice controller causes: the DC-DC power convertor to produce the firstvoltage in response to the input voltage detection circuit determiningthat an input voltage is equal to or greater than a threshold voltage,and the DC-DC power convertor to produce the second voltage in responseto the input voltage detection circuit determining that the inputvoltage is less than the threshold voltage.
 10. The electrical powersupply device according to claim 9, wherein a maximum value of the firstvoltage is 20 volts and a minimum value of the second voltage is 3.2volts.
 11. The electrical power supply device according to claim 9,wherein the device controller further comprises a processor andnon-volatile memory which contains instructions which causes the DC-DCpower convertor to produce the first voltage in response the inputvoltage detection circuit determining that an input voltage is equal toor greater than a threshold voltage and which causes the DC-DC powerconvertor to produce the second voltage in response to input voltagedetection circuit determining that the input voltage is less than thethreshold voltage.
 12. An electrical power supply device configured tointerface with a start-stop controller within a vehicle, comprising: aDC-DC power convertor configured to produce a first voltage or a secondvoltage that is less than the first voltage; and a means for commandingthe DC-DC power convertor to produce the first voltage in response to arun signal from the start-stop controller and for commanding the DC-DCpower convertor to produce the second voltage in in response to a stopsignal from the start-stop controller.
 13. The electrical power supplydevice according to claim 12, wherein a maximum value of the firstvoltage is 20 volts and a minimum value of the second voltage is 3.2volts.
 14. The electrical power supply device according to claim 12,further comprising means for establishing communication between thestart-stop controller and the means for commanding the DC-DC powerconvertor, wherein the means for establishing communication comprises atleast one selected from a list consisting of a controller area network(CAN) transceiver, a local interconnect network (LIN) transceiver, a USBtransceiver, and an input voltage detection circuit.
 15. The electricalpower supply device according to claim 12, wherein the electrical powersupply device further comprises means for communication with a USBtransceiver, wherein the means for commanding the DC-DC power convertorcauses: the DC-DC power convertor to output the first voltage inresponse to the USB transceiver receiving a first USB signal indicatingthe run signal from the start-stop controller; and the DC-DC powerconvertor to output the second voltage in response to the USBtransceiver receiving a first USB signal indicating the run signal fromthe start-stop controller.
 16. The electrical power supply deviceaccording to claim 12, wherein the electrical power supply devicefurther comprises means for communication with a USB transceiver whichis in communication with the start-stop controller, wherein the meansfor commanding the DC-DC power convertor causes: negotiation of a powerdelivery contract with a consumer device at a first output power inresponse to the USB transceiver receiving a first USB signal indicatingthe run signal from the start-stop controller, and renegotiation of thepower delivery contract with the consumer device at a second outputpower less than the first output power in response to the USBtransceiver receiving a first USB signal indicating the run signal fromthe start-stop controller.
 17. The electrical power supply deviceaccording to claim 16, wherein the means for commanding the DC-DC powerconvertor causes renegotiation of the power delivery contract with theconsumer device at a first output power in accordance with the USBtransceiver transmitting the first USB signal indicating that thestart-stop controller has transmitted the run signal.
 18. The electricalpower supply device according to claim 16, wherein the first outputpower is 100 watts and the second output power is 15 watts.